Overlapping functions of lysosomal acid phosphatase (LAP) and tartrate-resistant acid phosphatase (Acp5) revealed by doubly deficient mice

Development ◽  
2001 ◽  
Vol 128 (23) ◽  
pp. 4899-4910
Author(s):  
Anke Suter ◽  
Vincent Everts ◽  
Alan Boyde ◽  
Sheila J. Jones ◽  
Renate Lüllmann-Rauch ◽  
...  

To date, two lysosomal acid phosphatases are known to be expressed in cells of the monocyte/phagocyte lineage: the ubiquitously expressed lysosomal acid phosphatase (LAP) and the tartrate-resistant acid phosphatase-type 5 (Acp5). Deficiency of either acid phosphatase results in relatively mild phenotypes, suggesting that these enzymes may be capable of mutual complementation. This prompted us to generate LAP/Acp5 doubly deficient mice. LAP/Acp5 doubly deficient mice are viable and fertile but display marked alterations in soft and mineralised tissues. They are characterised by a progressive hepatosplenomegaly, gait disturbances and exaggerated foreshortening of long bones. Histologically, these animals are distinguished by an excessive lysosomal storage in macrophages of the liver, spleen, bone marrow, kidney and by altered growth plates. Microscopic analyses showed an accumulation of osteopontin adjacent to actively resorbing osteoclasts of Acp5- and LAP/Acp5-deficient mice. In osteoclasts of phosphatase-deficient mice, vacuoles were frequently found which contained fine filamentous material. The vacuoles in Acp5- and LAP/Acp5 doubly-deficient osteoclasts also contained crystallite-like features, as well as osteopontin, suggesting that Acp5 is important for processing of this protein. This is further supported by biochemical analyses that demonstrate strongly reduced dephosphorylation of osteopontin incubated with LAP/Acp5-deficient bone extracts. Fibroblasts derived from LAP/Acp5 deficient embryos were still able to dephosphorylate mannose 6-phosphate residues of endocytosed arylsulfatase A. We conclude that for several substrates LAP and Acp5 can substitute for each other and that these acid phosphatases are essential for processing of non-collagenous proteins, including osteopontin, by osteoclasts.

Author(s):  
José A. Serrano ◽  
Hannah L. Wasserkrug ◽  
Anna A. Serrano ◽  
Arnold M. Seligman

As previously reported (1, 2) phosphorylcholine (PC) is a specific substrate for prostatatic acid phosphatase (PAP) as opposed to other acid phosphatases, e.g., lysosomal acid phosphatase. The specificity of PC for PAP is due to the pentavalent nitrogen in PC, a feature that renders PC resistant to hydrolysis by all other acid phosphatases. Detailed comparative cytochemical results in rat tissues are in press. This report deals with ultracytochemical results applying the method to normal and pathological human prostate gland.Fresh human prostate was obtained from 7 patients having transurethral resections or radical prostatectomies. The tissue was fixed in 3% glutaraldehyde- 0.1 M cacodylate buffer (pH 7.4) for 15 min, sectioned at 50 μm on a Sorvall TC-2 tissue sectioner, refixed for a total of 2 hr, and rinsed overnight in 0.1 M cacodylate buffer (pH 7.4)-7.5% sucrose.


1991 ◽  
Vol 277 (3) ◽  
pp. 631-634 ◽  
Author(s):  
A R Hayman ◽  
A J Dryden ◽  
T J Chambers ◽  
M J Warburton

Tartrate-resistant acid phosphatases have been isolated from a number of sources. These enzymes consist of one subunit (Mr 30,000-40,000) or two dissimilar subunits (Mr 15,000-20,000). Previously we isolated the enzyme from human osteoclastomas, as a two-subunit protein. By Northern blotting and hybridization with radiolabelled oligonucleotides corresponding to the N-terminal sequences of the two subunits, we demonstrate here that the enzyme is transcribed as one mRNA which is translated in vitro to produce a single polypeptide of approx. Mr 33,000. Transcription as a single mRNA species is also the case in other tissues. These results suggest that the osteoclastoma enzyme undergoes post-translational modification in the form of cleavage of a single peptide bond to give a disulphide-bonded two-subunit protein.


1997 ◽  
Vol 272 (30) ◽  
pp. 18628-18635 ◽  
Author(s):  
Paul Saftig ◽  
Dieter Hartmann ◽  
Renate Lüllmann-Rauch ◽  
Joachim Wolff ◽  
Meike Evers ◽  
...  

1972 ◽  
Vol 20 (7) ◽  
pp. 487-498 ◽  
Author(s):  
CHI-WEI LIN ◽  
WILLIAM H. FISHMAN

Biochemical methods have been employed to characterize and separate acid phosphatases from lysosomal and microsomal fractions in order to decide whether different isoenzymes reside in these subcellular locations. Microsomal and lysosomal fractions of mouse kidney homogenate were isolated by differential centrifugation. Acid phosphatase of lysosomal fraction goes into solution after lysosomes have been repeatedly frozen and thawed, whereas acid phosphatase of microsomal fraction is firmly bound to the membrane and is freed of contamination by lysosomal enzyme after ultrasonication and centrifugation. The membrane-bound microsomal acid phosphatase is labile at 37°C, pH 4.9, more active toward phenolic substrates (phenyl phosphate and p-nitrophenyl phosphate) than β-glycerophosphate, α-naphthol phosphate or naphthol AS-BI phosphate. It also has a higher pH optimum (6.3), is resistant to l-tartrate and oxalate inhibition and has a slower electrophoretic migration rate in Triton X-100-impregnated polyacrylamide gels. The free lysosomal acid phosphatase is relatively heat-stable, is less active against phenolic substrates, is sensitive to l-tartrate and oxalate inhibition, has a lower pH optimum (5.6) and has a faster migration rate in electrophoresis. These two acid phosphatases can also be separated by diethylaminoethyl-cellulose chromatography. This study thus demonstrated the existence of an acid phosphatase isoenzyme in the microsomal membrane with different biochemical properties from the lysosomal isoenzyme of acid phosphatase.


1965 ◽  
Vol 121 (5) ◽  
pp. 727-738 ◽  
Author(s):  
Kazuhisa Saito ◽  
Emanuel Suter

Experiments are reported dealing with the increase of lysosomal acid hydrolases induced by BCG infection. Acid hydrolases were determined quantitatively in peritoneal MP, liver homogenate, and plasma of normal and BCG-infected mice. A significant increase of acid phosphatase, ß-glucuronidase, and cathepsin was found in MP and liver homogenate of BCG-infected mice. In plasma also a significant increase of acid phosphatase and ß-glucuronidase was noticed. The results of the determination of the enzymes in centrifugally separated subcellular fractions of liver homogenate indicated clearly that the acid hydrolases associated mainly with the "large granular" fraction, which consists of mitochondria, lysosomes, and microsomes and that infection with BCG caused significant increase of the enzymes specifically in this fraction. Differences in the pattern of location among centrifugally separated fraction of liver homogenate were observed between acid phosphatase and the other two acid hydrolases. MP cultured in vitro doubled their acid phosphatases content within 24 hours, whereas ß-glucuronidase rather decreased in the same cells.


1989 ◽  
Vol 35 (1) ◽  
pp. 86-89 ◽  
Author(s):  
K B Whitaker ◽  
T M Cox ◽  
D W Moss

Abstract We describe an immunoassay for human band-5 acid phosphatase in which antibodies to porcine uteroferrin, immobilized on Sepharose particles, are used. Band-5 acid phosphatase is the tartrate-resistant isoenzyme normally expressed in tissue macrophages such as osteoclasts and alveolar macrophages. The immunoassay is similar in reproducibility and sensitivity to assays based on inhibition by d-tartrate. However, compared with the latter, the greater specificity of the immunoassay makes it markedly less susceptible to errors arising from the presence of non-band-5 acid phosphatases, e.g., from prostate.


2007 ◽  
Vol 80 (6) ◽  
pp. 400-410 ◽  
Author(s):  
Helen C. Roberts ◽  
Lynda Knott ◽  
Nicholas C. Avery ◽  
Timothy M. Cox ◽  
Martin J. Evans ◽  
...  

Author(s):  
W. Allen Shannon ◽  
José A. Serrano ◽  
Hannah L. Wasserkrug ◽  
Anna A. Serrano ◽  
Arnold M. Seligman

During the design and synthesis of new chemotherapeutic agents for prostatic carcinoma based on phosphorylated agents which might be enzyme-activated to cytotoxicity, phosphorylcholine, [(CH3)3+NCH2CH2OPO3Ca]Cl-, has been indicated to be a very specific substrate for prostatic acid phosphatase (PAP). This phenomenon has led to the development of specific histochemical and ultracytochemical methods for PAP using modifications of the Gomori lead method for acid phosphatase. Comparative histochemical results in prostate and kidney of the rat have been published earlier with phosphorylcholine (PC) and β-glycerophosphate (βGP). We now report the ultracytochemical results.Minced tissues were fixed in 3% glutaraldehyde-0.1 M phosphate buffered (pH 7.4) for 1.5 hr and rinsed overnight in several changes of 0.05 M phosphate buffer (pH 7.0) containing 7.5% sucrose. Tissues were incubated 30 min to 2 hr in Gomori acid phosphatase medium (2) containing 0.1 M substrate, either PC or βGP.


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